Google, Microsoft and Apple are all looking to tap solar, wind and hydroelectric power sources

Google has announced plans to continue its rollout of solar energy plants in the U.S. with one of its larger investments to date: $80 million for six new facilities.

So far, Google has committed over $1 billion to wind and solar power plants that create clean energy and generate "attractive financial returns," it said in a blog post.

The new plants, which will be built in California and Arizona, are expected to generate 160 megawatts (MW) of electricity, enough to power 17,000 typical U.S. homes. They are expected to be operational by early 2014.

The 17.5 megawatt/22 megawatt Victor Phelan project, located in San Bernardino, Calif., is part of six Recurrent Energy developed projects acquired by Google and KKR. (Image: Recurrent Energy)

"You'd think the thrill might wear off this whole renewable energy investing thing after a while. Nope -- we're still as into it as ever, which is why we're so pleased to announce our 14th investment," Google wrote on its official blog.

Last year, Google invested $200 million in a 161MW wind farm in Oldham County, Texas. In 2011, Google invested $280 million to create a fund that helped solar systems provider SolarCity finance more residential solar installations across the country.

"SolarCity works with a customer to design a solar system for their home. Investors like Google purchase the system up front and, in return, receive a portion of lease payments from the homeowner along with Solar City," Google wrote in an announcement about the deal."

All together, Google's 14 renewable power facilities will be able to generate 2 billion watts (gigawatts) of energy, enough to power 500,000 homes or all of the public elementary schools in New York, Oregon, and Wyoming for one year, the company said.

The latest solar power investment is similar to one Google made in 2011, when it partnered with global investment firm KKR and invested $94 million in four solar facilities built by Recurrent Energy.

"Those facilities have since started generating electricity, and we've committed hundreds of millions more -- more than $1 billion in total -- to renewable energy projects around the world," Google said in its blog. "These investments are all part of our drive toward a clean energy future -- where renewable energy is abundant, accessible and affordable.

According to the latest data, 6.8 gigawatts of wind power was added in the U.S. in 2011, a 31% increase over 2010. That 2011 jump brought the cumulative wind power capacity for the U.S. to 47 gigawatts, according to a study published by the Lawrence Berkeley National Laboratory.

The latest data from the Solar Energy Industries Association (SEIA) shows that the U.S. now has more than 6.4 gigawatts of installed solar electric capacity, enough power for more than a million households. This year is expected to exceed all others for new solar installations.

Google officials could not be reached for comment on the solar plant plans/